Contact lenses are often treated with conditioning solutions and/or cleaning materials to condition or clean the lenses. Typical conditioning solutions include moisturizing material and eye conditioning solutions. Cleaning of contact lenses, both hard and soft, has involved difficulties.
It is important to maintain the structural integrity and optical clarity of contact lenses while applying cleaning materials in a safe and efficient manner, to thoroughly scour and clean the lenses without changing the power of the lenses or scratching the lenses in any way, and thus avoid degredation of the optical qualities of the lenses.
A variety of cleaning solutions and methods are known. Such methods include those described in U.S. Pat. No. 4,533,399 and the Background of the Invention of that patent. U.S. Pat. No. 4,533,399 describes a method of cleaning contact lenses by providing a moistened, non-woven fibrous web and rubbing the lens with the fibrous web in the presence of a cleaning solution. The patent further defines other known cleaning methods, including use of sponges of synthetic foam such as urethane, as disclosed in U.S. Pat. Nos. 3,063,083 and 4,187,574. Other sponge like products are available and are stated to be described in Japanese Kokai, JP No. 82,105,427, with still another lens cleaning method using a cleaning and polishing cloth described in U.S. Pat. No. 4,357,173.
The art has considered prior cleaning materials to have problems in some cases; as for example, lack of abrasive power to remove deposits, tendency to plug too rapidly, high cost, difficulties in handling contact lenses while still applying proper abrading power and contamination of the lens surface by allowing the skin to contact the contact lenses in certain cases.